Biochemical, Hematological, and Pathological Observations of Black Bears in the Smoky Mountains
Date of Award
Master of Science
Wildlife and Fisheries Science
Michael R. Pelton
John C. New, Richard Strange
Selected tissues were collected from black bears in the Smoky Mountains between May 1976 and September 1980. Information related to the pathology of bears was accumulated and analyzed. Specimens were obtained from 290 bears.
Pathological studies included whole blood and serum biochemical parameters, a parasitic and infectious disease survey and gross and histological evaluation of tissues obtained from post mortem examinations. Whole blood specimens were analyzed for percent cell volume (PCV), hemoglobin (HGB), red blood cell count (RBC), white blood cell count (WBC), platelet count, estimated sedimentation rate (ESR), and reticulocyte count. Calculations were determined for erythrocytes including mean cell volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). One hundred eighty-one peripheral blood smears were stained and hematopoietic tissues were examined microscopically to determine normal ranges and irregularities of pathologic significance. Differential counts of leukocytes were performed to determine relative abundance of cell series types. Erythrocytes were examined for irregularities in hemoglobin concentration, prematurity, inclusion bodies, and structural integrity.
One hundred thirty sera samples were analyzed for 24 biochemical parameters including glucose, blood urea nitrogen (BUN), creatinine, BUN/creatinine ratio, sodium, potassium, chloride, carbon dioxide, uric acid, calcium, phosphorus, total protein, albumin, iron, cholesterol, triglyceride, alkaline phosphatase, lactic dehydrogenase (LDH), serum glutamicoxalacetic transaminase (SGOT), creatinine phosphokinase (CPK), total bilirubin, globulin, and albumin/globumin ratio. Electrolytic balance was also calculated. Statistical tests were performed on data for normal value and abnormal value associations of pathologic significance.
Urinalysis including biochemical and microscopic observations was performed on 8 urine specimens collected from immobilized bears.
Antibody titers for 5 serovars of Leptospira interrogans were determined from sera samples from 240 different bears. Fifteen bears were reactors (>1:50) for L. canicola, 36 bears exhibited titers for L. grippotyphosa, and 1 bear had a titer for L. hardjo. A total of 64 bears were reactors (26.6%). Nine bears were reactors for more than one serovar.
One hundred seventy-eight bears were tested serologically for canine distemper virus. Fifty-two reactors (29.2%) were determined for 1978-79 but no reactors were found in 1977 (n=47).
Antibody titers were examined for 2 serotypes of Brucella. Two hundred forty bears were tested for Brucella canis and 67 were tested for B. abortus; no reactors were determined.
Sixty-seven sera samples were submitted for antibody titers to infectious bovine rhinotracheitis, swine parvovirus, and pseudorabies. All specimens were collected during the 1978-79 period. No reactors were found. Sixty samples were negative for canine parvovirus titers.
Attempts to culture Bordetella bronchiseptica from 42 nasal swab specimens were negative. Fifty sera samples were tested for Bordetella antibodies but no reactors were observed. Forty-two sera, nasal, and rectal specimens were negative for swine influenza.
While performing whole blood cell morphologic observations, microfilariae of Dirofilaria ursi were observed. A total of 205 whole blood samples were examined for the presence of microfilaria. One hundred sixty-eight (81.9%) of the samples contained this parasite. Only 10 diaphragm specimens were available for determination of Trichinella spiralis larvae; no larvae were found.
Very little information was obtained from the post mortem examination of 10 bear carcasses. Fifty-three carcasses or carcass remnants were examined in the field. Radiologic examinations were performed for determination of the presence of lead or other artifacts related to illegal hunting activity. Forty carcasses were determined to have been illegally killed. The use of radiologic techniques to assist in the post mortem examination of wildlife proved to be a valuable tool.
The prevalence of antibody titers to infectious diseases and the presence of D. ursi provided information on the conditional status of bears. A descriptive epidemiological approach to the temporal and spatial aspects of the observations was used. Based on the information accumulated, the bear population in the Smoky Mountains appears to be in good condition. The influence of infectious diseases is inapparent. Development of wildlife forensic techniques and their determinations provided additional information previously not available for the protected bears in the Great Smoky Mountains National Park.
Cook, William Joseph, "Biochemical, Hematological, and Pathological Observations of Black Bears in the Smoky Mountains. " Master's Thesis, University of Tennessee, 1982.